Trenchless method

Primus Line® is installed trenchless. That means: No more construction pits that are hundreds of metres or several kilometres long.

Two pits or existing chambers are absolutely sufficient for the rehabilitation of pressure pipelines. Learn here how a trenchless rehabilitation works with Primus Line®.

Preparation

Shutdown of the pipeline

Before the rehabilitation can begin the pipeline has to be shut down according to relevant rules and standards.

It is at the discretion of the operator whether or not to establish a provisional supply.

Establishing access

Small construction pits or existing chambers: That is all the space necessary for the installation of Primus Line®. Only two are required for every rehabilitation section. If necessary – junctions for example – additional pits are possible.

Rope winches are placed at the start and end pit for further work steps.

Inspection of the host pipe

Deposits are no rarity in old pipelines. A clear picture of the condition in the rehabilitation section is immensely important for a successful installation of Primus Line®.

Visual inspection systems with high-resolution cameras and a large movement range provide not only detailed recordings of the inside of the pipe, which are essential for a precise preparation of the pipe cleaning measure. They also pull through a pilot rope for the winches placed at start and end pit.

Cleaning of the host pipe

Proven mechanical procedures with spring steel scrapers and rubber discs reliably clean the pipe from encrusted deposits and loose debris.

That way a free inner diameter is established for the installation of the liner.

Installation

Installation of the liner

Assembly of the pulling head

Beore installation the liner is fitted with a pulling head that is designed for forces of up to 100 kN. A swivel in the pulling connection with the winches prevents the liner from twisting on its way from start to end pit.

Installation

The liner is delivered folded. That way Primus Line® can be installed even in pipes with the same nominal diameter.

Adhesive tape keeps the liner in this U-shape until it is pressurised with about 500 mbar. Subsequently it assumes its round form.

Assembly of the connectors

Assembly of the M-Connector

The M-Connectors by Primus Line consist of a bushing and a core. With the M-Connector a pull-proof unit out of liner and connector is established by hydraulically pressing the core into the bushing.

Screwed to a flange on the host pipe a leak-free pull-proof connection between is established that forms a closed annulus.

Assembly of the R-Connector

The R-Connectors by Primus Line consist of a core and a bushing.

With the R-Connectors the core is first fitted into the bushing with an anti-friction agent. The bushing has a malleable steel jacket inside that is pushed onto the liner and into an indentation on the core by a two-component resin. The result is a pull-proof unit of liner and connector.

A leak-free pull-proof connection with the host pipe can be established with a flange or welding solution.

Pressure test

The pressure test according to relevant rules and standards for fluid and gaseous media ensures the stability and especially leak-tightness of the section rehabilitated with Primus Line®. Specifically for water applications the liner is additionally disinfected.

Reintegration of the rehabilitated pipeline

Integration of a fitting piece

In order for the line to be properly recommissioned a fitting piece is installed to reconnect the rehabilitated section with the pressure pipeline network.